1. Field of the Invention
The invention relates to a pressure damper with an enclosed gas mass for volume compensation in a vibration damper.
2. Discussion of the Prior Art
Enclosed gas masses are used, for example, when a medium is to be placed and held under pressure, but no mixing with an open pressure fluid is permitted. One widespread use is in piston-cylinder aggregates such as vibration dampers. A vibration damper with an enclosed gas mass is known, for example, from U.S. Pat. No. 3,294,391. The enclosed gas mass serves to compensate for the volume of the piston rod or the piston that submerges into the vibration damper.
A problem with such enclosed gas masses is that gas diffuses through the wall of the enveloping body into the damping medium of the vibration damper. If a certain level of gas emerges in this fashion, the vibration damper becomes limited in function, for example, or even unusable. One method of reducing this problem is to use certain feed gases, such as nitrogen. However, even nitrogen diffuses through the conventional enveloping bodies, which frequently consist of a rubber material or an elastomer, particularly at high temperatures.